Risk of Orthopedic Surgical Site Infections in Patients with Rheumatoid Arthritis Treated with Antitumor Necrosis Factor Alfa Therapy

Table 1

Newcastle-Ottawa Cohort Quality Assessment Scale, adapted for review purposes, as description from authors. Acronym: RA: rheumatoid arthritis.

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Selection

(1) Representativeness of the exposed cohort

 (a) truly representative of the average RA patient in the

 community*

 (b) somewhat representative of the average RA patient in the

 community*

  (c) selected group of users e.g., nurses, volunteers

  (d) no description of the derivation of the cohort

(2) Selection of the nonexposed cohort

  (a) drawn from the same community as the exposed cohort*

  (b) drawn from a different source

  (c) no description of the derivation of the nonexposed cohort

(3) Ascertainment of exposure

  (a) secure record (e.g., surgical records)*

  (b) structured interview *

  (c) written self-report

  (d) no description

(4) Demonstration that outcome of interest was not present at start

 of study

 (a) yes*

 (b) no

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Comparability

(1) Comparability of cohorts on the basis of the design or analysis

 (a) study controls for surgical time*

 (b) study controls for any additional factor *

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Outcome

(1) Assessment of outcome

  (a) independent blind assessment*

  (b) record linkage*

  (c) self-report

  (d) no description

(2) Was followup long enough for outcomes to occur?

  (a) yes (1 year)

  (b) no

(3) Adequacy of followup of cohorts

  (a) complete follow up—all subjects accounted for*

  (b) subjects lost to followup unlikely to introduce bias—small

 number lost—>80% follow up, or description provided of those

 lost*

  (c) followup rate < 80% and no description of those lost

  (d) no statement

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*Studies were considered of high quality if they had at least one asterisk in each area, and the sum of the asterisks were equal to or greater than five.